Medical Definition of phosphorus pentoxide
: a compound known in various polymeric forms (P2O5)x that is obtained usually by burning phosphorus in an excess of dry air, occurs as a white powder that reacts vigorously and sometimes explosively with water to form phosphoric acids irritating to the skin and mucous membranes, and is used chiefly as a drying agent, as a condensing agent in organic synthesis, and in making phosphoric acids and derivatives
Seen and Heard
What made you want to look up phosphorus pentoxide? Please tell us where you read or heard it (including the quote, if possible).